The receptacles in this document are more particularly those intended to contain dangerous substances, such as radioactive ones, to be carried by pneumatic means in pipes between product filling, sampling, analysis and reject stations making up the measurement installation. As regards the prior art, the receptacle shown on FIG. 1 includes a small jug 1 which, is intended to contain a product to be analysed, and a cursor 2 which surrounds the small jug 1. The small jug 1 is closed by a stopper 3 and the cursor 2, which like the small jug has an opening, is closed by a cap 4. The small jug 1 is housed with a large amount of play in the cursor 2. The cursor 2 is fitted with two annular flanges 5 and 6 enabling it to easily slide in pneumatic pipes. The flexible elastomer stopper 3 is composed of a circular internal lip 7 moulded onto the opening wall of the small jug 1 with a flat pricking surface 8 and intended to be pierced by needles for filling the small jug 1 and taking samples from the small jug 1, and a skirt 9 folded back around the opening edge of the small jug 1 in the position shown where the small jug 1 and cursor 2 are closed. The lower lip 7 is provided at its end with a swelling 10 which makes it possible to retain against the pricking surface 8 a drop catcher 11 composed of a ring 12 mounted in the internal lip 7 and a valve 13 parallel to the pricking surface 8 and whose r ole, as its name indicates, is to wipe dry the needles extracted from the small jug 1, thus retaining the liquid drop which could be suspended from it. Before being folded back, the skirt 9 significantly extends the internal lip 7 opposite the pricking surface 8.
The cursor 2 is provided with a hole 14 in front of the pricking surface 8 so as to allow the needles to reach the small jug 1. As for the cap 4, this is made of flexible plastic and locked by virtue of an internal edge 15 at its end on an external swelling 16 of the opening of the cursor 2.
This conception is subject to a large number of drawbacks which considerably reduce its advantages. In particular, it is necessary to carry out samplings by means of needles as it is impossible to temporarily open the small jug 1 by removing the stopper 3 : the dangerous nature of the substances carried means that the small jugs be remote-handled and the only tools available in the existing installation are pliers able to remove the stopper 3 but not replace it as the skirt 9, which remains folded back, opposes any new driving in of the stopper 3 by rubbing against the edge of the small jug 1 and is too flexible so as to be able to straighten it.
The contaminating liquid droplets, which may appear despite the drop catcher 11 when the needle comes out of the pricking surface 8, flow firstly between the small jug 1 and the cursor 2 and permanently pollute them, and secondly remain on this pricking surface 8 with the result on account of the movements transmitted to the small jug/cursor unit to also pollute the sampling installation, the pipes of the pneumatic network and the station of the installation where the small jugs 1 have left the cursors 2 so as to be definitively open. The small jugs 1 and the cursors 2 shall be packed as dangerous waste at an extremely high cost as the infiltration of the liquid in the center of their walls established with the plastic materials used prevents the decontaminations from being effective.
The cap 4 can sometimes fall off in the pipes and requires dismantlings be made to recover the elements of the system with extremely restrictive precautions so as to maintain containment of the substances.
In practice, analyses are made on several small jugs 1 at the same time. The cursors 2 are marked by a coding but become unusable as soon as the small jugs 1 are extracted from the cursors 2, this operation for separating the small jug 1 from its cursor 2 being dictated by the type and analysis methods used : for example, the measurements for absorbing a radiation or requiring that the contents of the small jug 1 be poured into a tank after opening of the stopper 3. It then becomes impossible to match the small jugs 1 and the corresponding cursors 2 and thus definitely identify the samples, this resulting in a possible risk of confusion of the samples.
The small jug 1, produced by a method for blowing into an external mould, has an internal diameter which varies widely which compromises the accuracy of the measurements, such as the absorption measurements carried out with the aid of a ray which traverses the contents of the small jug 1.
Furthermore, the imperviousness between the small jug 1 and the stopper 3 is not very good and the vacuum, which is firstly established in the small jug 1, gradually ceases.
Finally, the sampling needles frequently pull up the drop catcher 11 from its housing instead of piercing it. The result is that the takings of samples comes to naught.